Plug-in hybrid
A plug-in hybrid electric vehicle (PHEV), plug-in hybrid vehicle (PHV), or plug-in hybrid is a hybrid electric vehicle which utilizes rechargeable batteries, or another energy storage device, that can be restored to full charge by connecting a plug to an external electric power source (usually a normal electric wall socket). A PHEV shares the characteristics of both a conventional hybrid electric vehicle, having an electric motor and an internal combustion engine (ICE); and of an all-electric vehicle, having a plug to connect to the electrical grid. Most PHEVs on the road today are passenger cars, but there are also PHEV versions of commercial vehicles and vans, utility trucks, buses, trains, motorcycles, scooters, and military vehicles. The cost for electricity to power plug-in hybrids for all-electric operation has been estimated at less than one quarter of the cost of gasoline in California. Compared to conventional vehicles, PHEVs reduce air pollution locally and dependence on petroleum. PHEVs may reduce greenhouse gas emissions that contribute to global warming, compared with conventional vehicles. PHEVs also eliminate the problem of range anxiety associated with all-electric vehicles, because the combustion engine works as a backup when the batteries are depleted, giving PHEVs driving range comparable to other vehicles with gasoline tanks. in geologic time | journal = Journal of Geophysical Research | volume = 110 | issue=C9 | pages=C09S05.1–C09S05.6 | year = 2005 | doi=10.1029/2004JC002625 | accessdate=2008-12-31 | bibcode=2005JGRC..11009S05A}} See reviewed by CalCars founder Felix Kramer (September 9, 2008) "T. Friedman's New Bestseller Hot, Flat & Crowded Touts Plug-Ins" Plug-in hybrids use no fossil fuel at the point of use during their all-electric range. Greenhouse gas emissions attributable to operation of plug-in hybrids during their all-electric range depend on the type of power plant that is used to meet additional demand on the electrical grid at the time and place where the batteries are charged. (See Greenhouse gas emissions, below.) If the batteries are charged directly from renewable sources off the electrical grid, then the greenhouse gas emissions are essentially zero. Other benefits include improved national energy security, fewer fill-ups at the filling station, the convenience of home recharging, opportunities to provide emergency backup power in the home, and vehicle-to-grid (V2G) applications.Simpson, A. (2006) [http://www.nrel.gov/docs/fy07osti/40485.pdf Cost-Benefit Analysis of Plug-in Hybrid Electric Vehicle Technology] National Renewable Energy Laboratory conference report CP-540-40485 accessed January 7, 2009 Several countries, including the United States and several European countries, have enacted laws to facilitate the introduction of PHEVs through grants and tax credits, emissions mandates, and by financing research and development of advanced batteries and other related technologies. Chinese battery manufacturer and automaker BYD Auto released the F3DM to the Chinese fleet market in December 2008Crippen, A. (December 15, 2008) "Warren Buffett's Electric Car Hits the Chinese Market, But Rollout Delayed For U.S. & Europe" CNBC. Retrieved December 2008.Balfour, F. (December 15, 2008) "China's First Plug-In Hybrid Car Rolls Out" Business Week. Retrieved December 2008. and began sales to the general public in Shenzhen in March 2010. General Motors began deliveries of the Chevrolet Volt in the United States in December 2010, becoming the first plug-in hybrid available for retail sales in the American market. , the number of series production highway legal plug-in hybrids available for retail sales is limited to over 15 models, including some limited production luxury sport cars, and available mainly in the United States, Canada, Western European countries, Japan and China. , over 260,000 highway-capable plug-in hybrid electric cars have been sold worldwide since December 2008. The Chevrolet Volt family, including its siblings Opel/Vauxhall Ampera, is the world's best selling plug-in hybrid with combined sales of over 87,000 units up to November 2014. The Toyota Prius PHV is the second top selling plug-in hybrid with global sales of over 65,300 units , followed by the Mitsubishi Outlander P-HEV with about 33,000 units . The United States is the market segment leader, with over 126,000 plug-in hybrids delivered , followed by the Netherlands with more than 32,000 units, and Japan with about 31,000 units. Global News 2007 *Google launches RechargeIT plug-in hybrid car initiative and unveils solar installation. Google.org to fund more than $10 million to accelerate plug-in hybrid and vehicle-to-grid technology. Google Press Center, June 18 Video Google.org RechargeIT: Plug-in Hybrids, about 5 mins., added: June 15, 2007 Greenhouse gas emissions The effect of PHEVs on greenhouse emissions is complex. Plug-in hybrid vehicles operating on all-electric mode do not emit harmful tailpipe pollutants from the onboard source of power. The clean air benefit is usually local because depending on the source of the electricity used to recharge the batteries, air pollutant emissions are shifted to the location of the generation plants. In the same way, PHEVs do not emit greenhouse gases from the onboard source of power, but from the point of view of a well-to-wheel assessment, the extent of the benefit also depends on the fuel and technology used for electricity generation. From the perspective of a full life cycle analysis, the electricity used to recharge the batteries must be generated from renewable or clean sources such as wind, solar, hydroelectric, or nuclear power for PEVs to have almost none or zero well-to-wheel emissions. pages=2–5 On the other hand, when PEVs are recharged from coal-fired plants, they usually produce slightly more greenhouse gas emissions than internal combustion engine vehicles. In the case of plug-in hybrid electric vehicle when operating in hybrid mode with assistance of the internal combustion engine, tailpipe and greenhouse emissions are lower in comparison to conventional cars because of their higher fuel economy. There has been much debate over the potential GHG emissions reductions that can be achieved with PHEV. A study by the Electric Power Research Institute reports that a 338 TW·h or 5.8% increase in power generation needed as a result of PHEV. In the same report the EPRI also states that CO2 emissions could increase by 430 million metric tons. The article concludes: :"In summary, the addition of PHEVs as a significant transportation option adds approximately 6% to the total national electricity demand in 2030 compared to the base case with no PHEVs. Due to the charging profile that results in most of this additional demand occurring during off-peak hours (late night/early morning) there is an increase in the need for baseload generation. The addition of coal-fired generation to meet this need for more baseload generation does not result in any significant differences in annual emissions of SO2, NO''x and Hg because of the caps on those pollutants. Therefore, any reductions in emissions of SO2, NO''x'' or Hg from non-electric generating sources would result in a net national decline in these emissions. However, it does result in an appreciable increase in CO2 and PM emissions as this analysis has not assumed any limits on CO2 or PM emissions''." A study by the American Council for an Energy Efficient Economy (ACEEE) predicts that, on average, a typical American driver is expected to achieve about a 15% reduction in net emissions compared to the driver of a regular hybrid, based on the 2005 distribution of power sources feeding the US electrical grid. The ACEEE study also predicts that in areas where more than 80% of grid-power comes from coal-burning power plants, local net emissions will increase,Kliesch, J. and Langer, T. (September 2006) "Plug-In Hybrids: an Environmental and Economic Performance Outlook" American Council for an Energy-Efficient Economy while for PHEVs recharged in areas where the grid is fed by power sources with lower emissions than the current average, net emissions associated with PHEVs will decrease correspondingly. A 2007 joint study by the Electric Power Research Institute (EPRI) and the Natural Resources Defense Council (NRDC) similarly found that the introduction of PHEVs into America’s consumer vehicle fleet could achieve significant greenhouse gas emission reductions.Knipping, E. and Duvall, M. (June 2007) "Environmental Assessment of Plug-In Hybrid Electric Vehicles Volume 1: Nationwide Greenhouse Gas Emissions" Electric Power Research Institute and Natural Resources Defense Council. Retrieved July 21, 2007. The EPRI-NRDC report estimates that, between 2010 and 2050, a shift toward PHEV use could reduce GHG emissions by 3.4 to 10.4 billion metric tons. The magnitude of these reductions would ultimately depend on the level of PHEV market penetration and the carbon intensity of the US electricity sector. In general, PHEVs can be viewed as an element in the "Pacala and Socolow wedges" approach which shows a way to stabilize emissions using a portfolio of existing techniques, including efficient vehicles. A 2008 study at Duke University suggests that for PHEV's to reduce greenhouse gas emissions more than hybrids a carbon pricing signal that encourages the development of low carbon power is needed.Williams, E.(November 2008) "Plug-in and regular hybrids: A national and regional comparison of costs and CO2 emissions." Nicholas School of the Environment at Duke University RAND also in 2008 studied the questions of a carbon tax, carbon cap and trade systems, increasing gasoline tax, and providing renewable energy subsidies under various economic conditions and vehicle type availabilities. RAND found that subsidies were able to provide a smoother transition to new energy sources, especially in the face of energy source price volatility, because subsidies can be structured according to relative costs between renewables and fossil fuel, while taxes and carbon trading schemes alone do not take relative prices of energy into account.Toman, M. et al. (2008) "Impacts on U.S. Energy Expenditures and Greenhouse-Gas Emissions of Increasing Renewable-Energy Use" RAND Environment, Energy, and Economic Development program (RAND Tech Rep. No. 384-1) The Minnesota Pollution Control Agency found that if Minnesota's fleet of vehicles making lengthy trips were replaced by plug-in hybrids, emissions per vehicle would likely decrease. However, unless more than 40% of the electricity used to charge the vehicles were to come from non-polluting sources, replacing the vehicles with non-plug-in hybrids would engender a larger decrease in emissions.Minnesota Pollution Control Agency (March 2007) "Air Emissions Impact of Plud-In Hybrid Vehicles in Minnesota's Passenger Fleet" Plug-in hybrids use less fuel in all cases, and produce much less carbon dioxide in short commuter trips, which is how most vehicles are used. The difference is such that overall carbon emissions would decrease if all internal combustion vehicles were converted to plug-ins. Argonne National Laboratory In 2009 researchers at Argonne National Laboratory adapted their GREET model to conduct a full well-to-wheels (WTW) analysis of energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles for several scenarios, considering different on-board fuels and different sources of electricity generation for recharging the vehicle batteries. Three US regions were selected for the analysis, California, New York, and Illinois, as these regions include major metropolitan areas with significant variations in their energy generation mixes. The full cycle analysis results were also reported for the US generation mix and renewable electricity to examine cases of average and clean mixes, respectively Report ANL/ESD/09-2 This 2009 study showed a wide spread of petroleum use and GHG emissions among the different fuel production technologies and grid generation mixes. The following table summarizes the main results: The Argonne study found that PHEVs offered reductions in petroleum energy use as compared with regular hybrid electric vehicles. More petroleum energy savings and also more GHG emissions reductions were realized as the all-electric range increased, except when electricity used to recharged was dominated by coal or oil-fired power generation. As expected, electricity from renewable sources realized the largest reductions in petroleum energy use and GHG emissions for all PHEVs as the all-electric range increased. The study also concluded that plug-in vehicles that employ biomass-based fuels (biomass-E85 and -hydrogen) may not realize GHG emissions benefits over regular hybrids if power generation is dominated by fossil sources. Oak Ridge National Laboratory A 2008 study by researchers at Oak Ridge National Laboratory analyzed oil use and greenhouse gas (GHG) emissions of plug-in hybrids relative to hybrid electric vehicles under several scenarios for years 2020 and 2030. Each type of vehicle was assumed to run per day and the HEV was assumed to have a fuel economy of . Report ORNL/TM-2007/150 The study considered the mix of power sources for 13 U.S. regions, generally a combination of coal, natural gas and nuclear energy, and to a lesser extend renewable energy. A 2010 study conducted at Argonne National Laboratory reached similar findings, concluding that PHEVs will reduce oil consumption but could produce very different greenhouse gas emissions for each region depending on the energy mix used to generate the electricity to recharge the plug-in hybrids. The following table summarizes the main results of the Oak Ridge National Laboratory study for the 2020 scenario: Environmental Protection Agency In October 2014, the U.S. Environmental Protection Agency published the 2014 edition of its annual report "Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends." For the first time, the report presents an analysis of the impact of alternative fuel vehicles, with emphasis in plug-in electric vehicles because as their market share is approaching 1%, PEVs began to have a measurable impact on the U.S. overall new vehicle fuel economy and emissions. EPA's report included the analysis of 12 all-electric passengers cars and 10 plug-in hybrids available in the market as model year 2014. For purposes of an accurate estimation of emissions, the analysis took into consideration the differences in operation between those PHEVs like the Chevrolet Volt that can operate in all-electric mode without using gasoline, and those that operate in a blended mode like the Toyota Prius PHV, which uses both energy stored in the battery and energy from the gasoline tank to propel the vehicle, but that can deliver substantial all-electric driving in blended mode. In addition, since the all-electric range of plug-in hybrids depends on the size of the battery pack, the analysis introduced a utility factor as a projection, on average, of the percentage of miles that will be driven using electricity (in electric only and blended modes) by an average driver. The following table shows the overall EV/hybrid fuel economy expressed in terms of miles per gallon gasoline equivalent (mpg-e) and the utility factor for the ten MY2014 plug-in hybrids available in the U.S. market. The study used the utility factor (since in pure EV mode there are no tailpipe emissions) and the EPA best estimate of the tailpipe emissions produced by these vehicles in real world city and highway operation based on the EPA 5-cycle label methodology, using a weighted 55% city/45% highway driving. The results are shown in the following table. In addition, the EPA accounted for the upstream emissions associated with the production and distribution of electricity required to charge the PHEVs. Since electricity production in the United States varies significantly from region to region, the EPA considered three scenarios/ranges with the low end of the range corresponding to the California powerplant emissions factor, the middle of the range represented by the national average powerplant emissions factor, and the upper end of the range corresponding to the powerplant emissions factor for the Rockies. The EPA estimates that the electricity GHG emission factors for various regions of the country vary from 346 g /kW-hr in California to 986 g /kW-hr in the Rockies, with a national average of 648 g /kW-hr. The following table shows the tailpipe emissions and the combined tailpipe and upstream emissions for each of the 10 MY 2014 PHEVs available in the U.S. market. National Bureau of Economic Research Most emission analysis use average emissions rates across regions instead of marginal generation at different times of the day. The former approach does not take into account the generation mix within interconnected electricity markets and shifting load profiles throughout the day. Published on line 2014-03-24. See pp. 251 An analysis by three economist affiliated with the National Bureau of Economic Research (NBER), published in November 2014, developed a methodology to estimate marginal emissions of electricity demand that vary by location and time of day across the United States. The study used emissions and consumption data for 2007 through 2009, and used the specifications for the Chevrolet Volt (all-electric range of ). The analysis found that marginal emission rates are more than three times as large in the Upper Midwest compared to the Western U.S., and within regions, rates for some hours of the day are more than twice those for others. Applying the results of the marginal analysis to plug-in electric vehicles, the NBER researchers found that the emissions of charging PEVs vary by region and hours of the day. In some regions, such as the Western U.S. and Texas, emissions per mile from driving PEVs are less than those from driving a hybrid car. However, in other regions, such as the Upper Midwest, charging during the recommended hours of midnight to 4 a.m. implies that PEVs generate more emissions per mile than the average car currently on the road. The results show a fundamental tension between electricity load management and environmental goals as the hours when electricity is the least expensive to produce tend to be the hours with the greatest emissions. This occurs because coal-fired units, which have higher emission rates, are most commonly used to meet base-level and off-peak electricity demand; while natural gas units, which have relatively low emissions rates, are often brought online to meet peak demand. This pattern of fuel shifting explains why emission rates tend to be higher at night and lower during periods of peak demand in the morning and evening. Related topic *Sustainable travel *Reduced dependence on cars Related Wikipedia content *wikipedia:Plug-in hybrid References External links *RechargeIT *HybridAutoInfo.com *HybridCars.com category:Sustpedia Category:Transport & planning Category:Air Pollution